The basic components of an Li/V.sub.x O.sub.y cell include a lithium anode, a separator, and a vanadium oxide cathode. The cathode is usually composed of an oxide of vanadium, such as vanadium pentoxide (V.sub.2 O.sub.5), and other components such as graphite and an electrolyte/binder.
During cell operation, incorporation of lithium in V.sub.2 O.sub.5 occurs. It is known that the Li/V.sub.2 O.sub.5 system heretofore in use has a multi-plateau discharge characteristic. Li/V.sub.2 O.sub.5 cells are known to have as many as 3 voltage steps above 2.0 volts. Gross plateaus appear at about 3.2 V, 2.4 V, and 2.1 to 2.2 V.
The relatively abrupt drop from about 3.0 volts to less than about 2.4 volts presents a major inconvenience for many electronic applications. Furthermore, it is known that the rechargeability of the Li/V.sub.2 O.sub.5 system is very sensitive to the lower voltage limit. If the battery is discharged to about 2.2 volts, the battery is practically impossible to recharge.
In U.S. Pat. No. 4,675,260, Sakurai et al describes binary and ternary cathode active materials of V.sub.2 O.sub.5 with at least one of P.sub.2 O.sub.5, TeO.sub.2, GeO.sub.2, Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.3 and B.sub.2 O.sub.3 and/or at least one metal oxide selected from the group consisting of MoO.sub.3 and WO.sub.3. Precursors of such binary and ternary products are heated to a melt and rapid quenched. The discharge profiles of such binary and ternary products contain significant plateaus which indicates that such products still possess some order and are not fully amorphous.
What is needed is a new cathode active material based on V.sub.2 O.sub.5, in a form which maintains its capacity and has good charge/discharge characteristics. What is also needed is a method to form such V.sub.2 O.sub.5 -based materials.